Industrial truck attachment



May 18, 1954 w, ZORN 2,678,742

INDUSTRIAL TRUCK ATTACHMENT 5 Sheets-Sheet 1 Filed Nov. 21 1951INVENTOR. WESL EY Z O R N May 18, 1954 w. ZORN 6 ,7

' INDUSTRIAL TRUCK ATTACHMENT Filed Nov. 21, 1951 5 Sheets-Sheet 2 y 18,1954 w. ZORN 2,678,742

I INDUSTRIAL TRUCK ATTACHMENT Filed Nov. 21, 1951 5 Sheets-Sheet 5ATTYS.

May 18, 1954 w, ZORN 2,678,742

7 INDUSTRIAL TRUCK ATTACHMENT Filed Nov. 21, 1951 5 Sheets-Sheet 4 [4 l7131 132 36 33 I3 1N l5 "1 A 1 1 I i i 1 1 g I7 27 i i 28 g t 11 I2 HINVENTOR.

WESLEY ZORN BYMM' May 18, 1954 w ZORN INDUSTRIAL TRUCK ATTACHMENT 5Sheets-She et 5 Filed NOV. 21 1951 INVENTOR. WESLEY 20 R N ATTYS.

Patented May 18, 1954 UNITED STATES TENT OFFICE INDUSTRIAL TRUCKATTACHMENT Wesley Zorn,

Equipment Company, poration of Michigan Chicago, 111., assigncr to ClarkBuchanan, Mich., a cor- 3 Claims.

My present invention relates generally to a load elevating mechanism,and, more specifically, is directed to a lift dump attachmentparticularly adapted for emptying a dump-bottom type hopper.

The present invention-constitutes an improvement over the liftdumpattachment'forming the subject matter of the copending application of E.Ryan Backofen and Wesley Zorn, Serial-No. 260,018, filed December 5,1951.

It is an object of my present invention to provide a lift dumpattachment having a sequentially operable 1 to 1 and 2 to 1 lift.

The attachment of my present invention is particularly adapted foremptyinga dump-bottom type hopper. This type of hopper comprises asubstantially rectangular body portion pivotally mounted at its rearend, about-a horizontalaxis, to a platform portion. The initiallyoperable 1 to 1 lift is provided to break open the hopper while the 2 to1 lift is provided to complete the opening of the hopper by causing theforward end of the body portion toswing upwardly and away from theforward end'of the platform portion.

It is another object of my present invention to provide a lift dumpattachment, as noted, which is of simple construction andeconomicaloperation.

The lift dump attachment of my present invention comp-rises first framemeans which is adapted to be secured to the load supporting carriage ofan industrial truck. Slidably mounted in the first frame means is secondframe means. effecting vertical movement/of the second'frame means. Acarriage assembly is mounted for movement within the secondframemeansand suitable stop means isprovided for causing the carriageassembly to move upwardly conjointly with the second frame means duringupward movement of the latter. Sprockets are rotatably mounted to thesecond frame means andchains are trained over the sprockets. The chainsare secured at their one ends tothe carriage assembly, and at theirother endsto means slidably mounted. along the actuating cylinder, whichmeans, in the specific embodiment'of my invention to be disclosedhereinafter, comprises a pair of slide members slidably mounted in guidetubes secured to opposite sides ofthe cylinder of the elevatinghydraulic assembly.

The slide members are adapted to engage the upper cap of the cylinder ofthe-elevating hydraulic assembly after the second frame means Ahydraulic assembly is provided for heightfor proupon continued upwardmovement of the secondframe means,

the chains will cause the carriage assembly to move upwardly at twicethe speed that the second frame means moves,

Now, in order to acquaint those skilled in the art with the manner ofconstructing and'using devices in accordance with the principles of mypresent invention, I shall describe, in connection with the accompanyingdrawings, a preferred embodiment of my present invention:

In the drawings:

Figure 1 isa perspective view-of an industrial truck to which issecured, at the forward'end thereof, the lift dump attachment of mypresent invention;

Figure 2 is a front elevational view of the lift dump attachment-ofFigure 1;

Figure 3 is a plan view of the lift dump attachment of Figure 2;

Figure 4 is a side elevational view of the'lift dum attachment of Figure2;-

Figure 5 is a perspective view of the industrial truck of Figure l withthe lift dump attachment in an elevated position;

Figure 6 is a diagrammatic frontelevational view of the lift dumpattachment .with theelements thereof'being shown in the same relativeposition as they are in Figure 2;

Figure 7 is a diagrammatic front elevational view of the lift dumpattachment with the elements thereof beingshown in the same relativeposition as they are in Figure 1; and

Figure 8 is a diagrammatic front elevational view of the lift dumpattachmentvrith the elements thereof being shown in the same'relativeposition as they are in Figure 5;

Referring now to Figure 1, there is shownan industrial truck,indicatedgenerally by the reference numeral it, having a pair of drivewheels I l-disposed at the forward end thereof, and a pair of steering.wheels 12 disposed at the rear end thereof. The truck I6 isprovided'with a conventional prime mover and drive means for effectingdriving of the forward wheels l 1. Mounted on the truck it is anoperators seat I3, and disposed forwardl" thereof is a hand steeringwheel M mounted on a steering column l5 which is operatively connectedin a conventionalmanner to the rear steering wheels l2. Pivotallymounted at the-forward end of the truck in is a conventional generallyvertically extending mast, indicated generallyby the reference numeralI6, which comprises a pair of opposed facing, vertically extending,outer channel members l1, in which are slidably mounted a pair ofvertically extending opposed facing channel members It. The outerchannel members l1, adjacent their upper ends, are maintained in spacedrelation by means of a brace 9. The inner slidable channel members l8,adjacent their upper ends, are interconnected by means of a cross head26, which has suitable connection to the upper end of the piston rod 2|of a hydraulic piston and cylinder assemblly, indicated generally by thereference numeral 22. The assembly 22 is secured, at its lower end, tothe outer channel members [1. Rotatably mounted on the cross head 26,about a horizontal axis, are a pair of sprocket gears 23 over which apair of chains 24 are trained. The chains 24, adjacent their one ends,have connection to a brace member, not shown, secured to the outer fixedchannel members l1, intermediate of the ends thereof. The chains 24,adjacent their other ends, are suitably connected to a load supportingcarriage which is mounted for upward and downward movement within theinner channel members I8. Detachably secured to the forward surface ofthe load supporting carriage are a pair of vertically spaced,transversely extending, frame members or fork bars 25 and 26.

Movement of the load supporting carriage within the inner channelmembers |8 is effected by selectively admitting fluid under pressure tothe lower end of the cylinder of the hydraulic piston and cylinderassembly 22. In this instance, the flow of fluid under pressure to thelower end of the cylinder causes the piston rod 2| to be urged upwardly,which, in turn, causes upward movement of the inner channel members l8,cross head 20, and sprocket gears 23. As the sprocket gears 23 are movedupwardly the chains 24, which as aforedescribed, are fixed at their oneends, rotate about the sprocket gears 23 thus urging the load supportincarriage upwardly. When it is desired tolower the load supportingcarriage, fluid under pressure is bled from the lower end of thecylinder of the assembly 22 thus permitting the piston rod 2| to movedownwardly under the weight of gravity.

Brackets 21 are secured to the outer sides of the outer channel membersl1, intermediate of the ends thereof, and pivotally mounted to thebrackets 21 are hydraulic piston and cylinder assemblies indicatedgenerally at 28 which are carried by the truck II). By the selectiveadmission of fluid under pressure to either the forward or rear ends ofthe hydraulic piston and cylinder assemblies 28, the mast assembly,indicat-ed generally at l6, may be tilted either forwardly orrearwardly.

Secured to the forward surfaces of the fork bars 25 and 26, in a mannerto be described fully hereinafter, is the lift dump attachment of mypresent invention. The attachment is particularly adapted for use with askid box or hopper of the character indicated generally at 3|. Thehopper 3| is of the dump bottom type and comprises a substantiallyrectangular body portion 32 pivotally mounted at its rear end, about ahorizontal axis, to a platform portion 33. The platform 33 is formedwith upturned sides 34 and is supported at its rear end on a pair oflegs 35. A transverse I-beam 36 is secured to the underside of theplatform 33 adjacent the forward end thereof. A suitable bracket 31 issecured to the rear end of the body portion 32.

The hopper 3| is normally in the position V a horizontal plate 60 shownin Figure 1, in which position a container is defined for storingarticles such as metal castings and the like. After the hopper 3| hasbeen filled with castings, or the like, and it is desired to empty thehopper 3|, the device of my present invention is adapted to effectraising of the rear end of the body portion 32 relative to the platform33. As shown in Figure 5, the platform 33 together with the upturnedsides 34, define an inclined chute, the lower end of which may bedirected toward another container or pile for conveying articles fromthe hopper 3| to the said container or pile.

The construction of the lift dump attachment of my present inventionshall now be described in detail.

A pair of spaced vertically extendin channel members 4| and 42, c-shapedin cross section, are secured at their lower ends to the forwardsurfaces of the fork bars 25 and 26. The channel members 4| and 42 aremaintained in proper spaced relation, at their upper ends, by means of ahorizontal channel brace member 43. The channel members 4|, 42 and 43define a first frame means. slidably mounted in the channel members 4|and 42, respectively, are channel members 44 and 45. The inner slidablechannel members 44 and 45 are interconnected at their upper ends by apair of spaced apart transversely extending brace members 46 and 41. Thebraces 46 and 41 are maintained in position by spacers 48 and 49. Thechannel members 44 and 45, brace members 46 and 41, and spacers 48 and49 define a second frame means which is slidably mounted in theafore-described first frame means.

Vertical movement of the inner slidable channel members 44 and 45,together with the transverse brace members 46 and 41, is effected bymeans of power actuated means which preferably comprises a centrallylocated hydraulic piston and cylinder assembly indicated generally bythe reference numeral 50. The hydraulic assembly 50 comprises a cylinder5| which is secured, at its lower end, by bolts 52 to a plate 53suitably secured, as by welding, to the front face of the lower fork bar26. The cylinder support plate 53 is reinforced by a substantiallytriangular gusset plate 54.

The upper end of the cylinder 5| is provided with a cylinder cap 55, towhich is secured, by bolts 56, a gland clamp plate 51 through whichextends a piston rod 58. The upper threaded end of the piston rod 58 issecured, by a nut 59, to which is secured between the inner channelbraces 46 and 41 intermediate of the ends thereof.

The hydraulic piston and cylinder assembly 50 is of the double actingtype, and, thus, when fluid is admitted to the lower end of cylinder 5|the piston rod 58 is urged upwardly, thereby moving the inner slide topbraces 46 and 41, together with the inner channel members 44 and 45,upwardly. When fluid under pressure is admitted to the upper end of thecylinder and fluid is simultaneously bled from the lower end of thecylinder 5| the piston rod 58 is urged downwardly thereby causing theinner channel top brace members 46 and 41, together with the innerchannels 44 and 45, to move downwardly within the outer channel members4| and 42.

Mounted for upward and downward movement within the inner slidablechannel members 44 and 45 is a carriage assembly indicated generally bythe reference numeral 1|. The carriage H comprises end plates 12- and 13which are disposed respectively adjacent the inner channel members 44and 45. Laterally extending pin. members I4 are fixed in the carriageend plate l2 and project intothe inner channel member 44-. Rotatablymounted on the outer ends of the pin members It are rollers I5 whichengage the inner surfaces of the leg portions of the inner channelmember A l. Laterally extending pin members I6 are fixed in the carriageend plate 13. The outer ends of the pin members I6 project into theinner channel member t5 and rotatably mounted on the projecting ends ofthe pin members I6 are rollers I! which engage the inner surfaces of theleg portions of the inner channel member 55.

Thrust roller blocks '88 and I9 are secured respectively to the carriageend plates '52 and'I3. The blocks 18 and I9 extend into the innerchannel members 44 and 45 and provide support for rollers it and FMwhich respectively engage the eight portions of the inner channelmembers id and A5.

$ecured to the forward edges of the carriage end plates I2 and I3,respectively, are lift brackets 32 and 35: which extend toward eachother. In terconnecting the lift brackets 82 and $3 is a transverselyextending main carriage plate 83 which is secured to the lift brackets82 and 83 respectively by bolts 35 and 86.

The junction of the carriage end plate I2 the lift bracket 82 isreinforced at the upper and lower ends thereof by gusset plates 88. Thejunction of the carriage end plate 13 and the lift bracket 82 isreinforced at the upper and lower ends thereof by gusset plates 89.W'elded to the inner channel members A l and 45, adjacent the lower endsthereof, are carriage bumper plates 9 and 9 i. The bumper plates 90' andSI act as stops for limiting downward movement of the carriage l!relative to the inner channel members M and 55.

Movement of the carriage H within the inner channel members ld and isaccomplished by chain means which shall now be described in deta l.Mounted intermediate of the inner channel braces 46 and ll, on'spacedapart shafts 93 and are compound sprockets 95 and 96. Trained over thesprockets 95 and 96, respectively, are

compound chains 9'! and 88. The chains 9'! and 92, at their one ends,are riveted to chain anchor pins 93 and its. The chain anchor pins 89and 595 respectively bolted to blocks HJI and I532 fixed to horizontalplates Hi3 and IM which are suitably secured to the rear surface of thecarriage plate 84. The mountings of the plates I 33 and le t to the maincarriage plate iii are reinforced by gusset plates I05 and N38.

The cylinder 5| of the hydraulic assembly 5 3 has secured along oppositesides thereof a pair of channel members I88 and I09. The outer ends ofthe leg portions of the cylinder channels its and I09 are interconnectedfor a portion of their length, adjacent the upper end, by closure platesii and III. The channels Hi8 and H13 and the respective closure platesIII) and II I define guide tubes for a purpose to be hereinafterdescribed. The cylinder channels I08 and Hit terminate immediatelybeneath the cylinder cap and the latter covers a portion of the opensection of the channels I08 and I09.

The other ends of the chains 9'! and Q8 extend downwardly into the openarea of the cylinder channels I58 and its and are riveted to 'rectangu'lar members H2 and H3 which are slidably mounted in'the guidetubesdefined by the channels I88 and I89 and the respective closure plates II0 and .I I I.

The upperedge of the maincarriageplate 8% has secured to its upper edgea pair of spaced block members I26 and I2'I' which provide a journalsupport for a transverse shaft I28. Secured to the shaft I28, adjacentthe block members I25 and I21, are a pair of J-shaped hook members I29and I39.

A pair of L-shaped horizontally spaced load supporting'fork frames I3Iand l32 are detachably secured along their verticallegs to theaforedescribed fork bars 25 and 26 immediately inwardly of the outerchannelmembers 4i and Q2.

The operation of the liftdumpattachment of my present invention is asfollows. When it is desired to dump the contents of a loaded hopper,the. industrial'truck ID is aligned with the hopper and the loadsupporting forks I3I' and I32 are inserted below the platform 33 betweenthe legs 35. The hopper 3| is then raised to an elevated position byselectively admitting fluid under pressure to the lower end ofthecylinder of the hydraulic assembly 22- of the truck mast I5. Whilethe hopper 3i is'being elevated as a unit, the elements of the lift dumpattachment remain in the positions shown inFigures 2 and 6. After thehopper 3I has been elevated to the desired height, fluid underpressureis admitted to the cylinder 5| of the hydraulic assembly 59 ofthe lift dump attachment which causes the inner channel top braces 46and A? to be raised together with the inner channel'members id and 45.The carriage assembly 'II of the lift dump attachment is also raised byvirtue of the stop members lit and SI engagingthe lower end. of thecarriage end plates i2 and 'I3. Through the initial range of movement ofthe inner slides 34 and 45, there is no relative movement between thecarriage ":I and the piston rod 58 and what-I term a 1 to 1 lift isprovided.

Now, during initial upward movement of the carriage ll, the hook membersI29and I36 engage the bracket 3'? of the hopper 3i causing the rear endof the latter to be moved upwardly. Duringupward movement of the rearend of the body portion 32 of the hopper 3i the forward end of the bodyportion 32 pivots upwardly and away from the platform portion 33. It hasbeen determined that a considerable-force is required to break open thehopper 3 I. For this reason, I have provided a liftdump attachment, asdescribed, wherein the carriage II: carrying the lift hooks I29 and I39moves initially at the same speed as the piston rod'58. This 1 to 1lift, however, it continued through the entire range of travel oi thecarriage I i, would require the attachment to be of considerable height.To overcome the lat ter objection, the above described chain and slidemeans are provided which cause the carriage 1i and lift hooks I 29 andI38 to move upwardly twice as fast as the piston rod 58, after thelatter has been actuated through a predetermined range.

As the piston rod-58 .of the hydraulic assembly 553 is urgedupwardly,the chain slides I I2 and I iii move upwardly within the cylinderchannels Eat and IE9, until the chain slides [I2 and I53 engage theunderside of the cylinder cap 55 as shown in Figure '7. At this point,the chain slides I 12 and I it are prevented from movingfurther upwardlyand a reaction'or anchor point is provided for the chains 9? and 98.

Upon further upward movement of the piston rod 58, the inner channel topbraces 45 and ill continue upwardly, and since the chains 91 and 98 areanchored at their one ends, the latter will travel over the sprockets 95and 95 causing the ends of the chains 91 and 98, secured to the carriageH, to move upwardly relative to the inner channels 44 and 45. Thus,through the final range of upward movement of the inner channels 44 and45, the carriage H is caused to move upwardly twice as fast as thepiston rod 53 providing what I term a 2 to 1 lift. I

From the afore-described operation of the lift dump attachment of mypresent invention, it will be readily apparent to those skilled in theart that the attachment provides for initial high force or power andsubsequent high speed hook travel. After the hopper 3| has beeninitially broken open, the force required to move the hopper to a fullopen position is less than the initial opening force required. Thus, the2 to 1 lift provides sufficient force to complete the opening of thehopper 3| after the latter has been initially broken open. By providinga sequentially operable 1 to l and 2 to 1 lift, the overall verticalheight of the attachment may be maintained at a minimum withoutsacrifice of operating efiiciency. The point at which the 2 to 1 liftbecomes effective may be varied by altering the lengths of the chains9'! and 98 which extend downwardly in the channels I68 and I09:

After the hopper 3| has been initially broken open, upward movement ofthe rear end of the body portion 32 causes the forward end of theplatform portion 33 to be drawn toward the industrial truck until theI-beam 3'5 engages the forward ends of the load supporting forks E3! andl32. At this point, the I-beam 36 acts to stop further movement of theplatform 33 toward the industrial truck and the hopper 3! will assumethe position shown in Figure while the elements of the lift dumpattachment will assume the positions shown in Fig. 8. With the hopper 3!in this position, the contents thereof will slide downwardly from thebody portion 32 along the inclined platform 33 which acts as a chute fordirecting the goods where desired.

The hopper 3| may be emptied at any predetermined height within thecapacity of the mast l6 of the industrial truck 10. After the hopper 3!has been emptied, fluid under pressure is selectively admitted to theupper end of the cylinder El and fluid is simultaneously bled from thelower end thereof thereby permitting the piston rod 58 to movedownwardly at which time the hopper 3| will return to the position shownin Figure 1.

Now, while I have shown and described what I believe to be a preferredembodiment of my present invention, it will be understood that variousmodifications and rearrangements may be made therein without departingfrom the spirit and scope of my invention.

I claim:

1. For use with an industrial truck having an upwardly and downwardlymovable load supporting carriage, the combination of a load elevatingmechanism comprising, first frame means secured to said load supportingcarriage, second frame means slidably mounted in said first frame means,a hydraulic assembly having a cylinder secured to said carriage and apiston rod secured to said second frame means, said cylinder having acap at the upper end thereof, a carriage assembly mounted for movementwith said second frame means, means for causing said carriage assemblyto move upwardly conjointly with said second frame means during initialupward movement of the latter, channel members secured to opposite sidesof said cylinder, sprogkets rotatably carried by said second framemeans, chains trained over said sprockets and secured at their one endsto said carriage assembly, slide members secured to the other ends ofsaid chains and being slidably mounted in said channel members, and saidslide members being adapted to engage the cylinder cap after said secondframe means has been raised a predetermined height for providingreaction points whereby upon continued upward movement of said secondframe means said chains will cause said carriage assembly to moveupwardly at a greater speed than the speed that said second frame meansmoves.

2. For use with an industrial truck having an upwardly and downwardlymovable load supporting carriage, the combination of a load elevatingmechanism comprising, first frame means secured to said load supportingcarriage, second frame means slidably mounted in said first frame means,a hydraulic assembly having a cylinder secured to said carriage and apiston rod secured to said second frame means, said cylinder having acap at the upper end thereof, a carriage assembly mounted for movementwithin said second frame means, stop means secured to the lower end ofsaid second frame means which engage said carriage assembly duringinitial upward movement of said second frame means for causing saidcarriage assembly to move upwardly conjointly with said second framemeans, guide tubes secured to opposite sides of said cylinder, sprocketsrotatably carried by said second frame means, chains trained over saidsprockets and secured at their one ends to said carriage assembly, slidemembers secured to the other ends of said chains and being slidablymounted in said guide tubes, the external peripheries of said slidemembers conforming to the internal peripheries of said guide tubes, andsaid slide members being adapted to engage the cylinder cap after saidsecond frame means has been raised a predetermined height for providingreaction points whereby upon continued upward movement of said secondframe means said chains will cause said carriage assembly to moveupwardly at twice the speed that said second frame means moves.

3. For use with an industrial truck having an upwardly and downwardlymovable load supporting carriage, the combination of a load elevatingmechanism comprising, a first pair of spaced vertically extendingchannel members secured to said load supporting carriage, a second pairof channel members slidably mounted in said first channel members, acrosshead extending transversely of the industrial truck andinterconnecting said second channel members adjacent the upper endthereof, a hydraulic assembly having a cylinder secured to said carriageand a piston rod secured to said cross-- head, said cylinder having acap at the upper end thereof, a carriage assembly mounted for movementwithin said second channel members, stop members secured to the lowerends of said second channel members which engage said carriage assemblyduring initial upward movement of said second channel members forcausing said carriage assembly to move upwardiy conjointly with saidsecond channel members, vertically extending guide tubes secured toopposite sides of said cylinder, sprockets rotatably carried by saidcrosshead, chains trained over said sprockets and secured at their oneends to said carriage assembly, slide members secured to the other endsof said chains and being slidably mounted in said guide tubes, the outerperipheries of said slide members conforming to the inner peripheries ofsaid guide tubes, and said slide members being adapted to engage thecylinder cap after said second channel members have been raised apredetermined height for providing reaction points whereby uponcontinued upward movement of said second channel members said chainswill cause said carriage assembly to move upwardly at twice the speedthat said second channel members move.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date Howell Nov. 5, 1940 Eaton July 27, 1943 Riemenschneider et a1July 13, 1948 Ulinski May 29, 1951 Herman Aug. 12, 1952

